Substrate processing apparatus

Abstract

A substrate processing apparatus which stably supplies a vaporized gas of liquid raw material to a processing chamber includes liquid raw material tanks storing a liquid raw material, a carrier gas supply line supplying a carrier gas to one of the tanks, a raw material supply line pressure-feeding to this tank the liquid raw material of the other tank, a carrier gas supply line feeding a carrier gas to the tank, a raw material supply line feeding to the processing chamber a vaporized gas of the liquid raw material of the tank, a mass flow controller which controls the flow rate of the carrier gas, a mass flow controller detecting the flow rate of the vaporized gas of the liquid raw material, and a feedback device feeding back a detection result of the mass flow controller to the former mass flow controller.

Description

INCORPORATION BY REFERENCE[0001]The present application claims priorities from Japanese applications JP2007-151605 filed on Jun. 7, 2007 and JP2008-126721, filed on May 14, 2008, the contents of which are hereby incorporated by reference into this application.BACKGROUND OF THE INVENTION[0002]This invention relates to substrate processing apparatuses and, in particular, to a substrate processing apparatus for processing a substrate by use of a vaporized gas of liquid raw material.[0003]As one example of this type of substrate processing apparatus, there is known an apparatus which employs the so-called bubbling technique for supplying a carrier gas to a liquid raw material tank which stores a liquid raw material to thereby feed a vaporized gas of the liquid raw material to a processing chamber. In this apparatus, the feed amount of the vaporized gas of liquid raw material to the processing chamber is controlled, in some cases, by the feed rate of a carrier gas being supplied to the l...

AI Technical Summary

Benefits of technology

[0007]A primary object of this invention is to provide a substrate processing apparatus capable of stabilizing the supply of an evaporated gas of liquid raw material to the processing chamber.

[0009]According to this invention, the feedback device is arranged to feed back the detection result of the detector device to the flow rate control device. Thus, it is possible to recognize the actual feed amount of the evaporated gas of the liquid raw material. It is also possible to precisely control the feed rate of the inactive gas without relation to variations of a liquid surface of the liquid raw materials in the first and second liquid raw material tanks. This makes it possible to stabilize the feed rate of the evaporated gas of liquid raw material to the processing chamber. Therefore, it is possible to suppress unwanted production of particles otherwise occurring due to reliquefaction of the evaporated gas of liquid raw material and flow blockage or “clogging” at a gas feed nozzle which is provided within the processing chamber and also possible to improve uniformity of the thickness of a film to be formed on the substrate.

Problems solved by technology

In this case, it is possible to control the feed rate of the carrier gas; however, it is impossible to recognize the actual feed rate of the evaporated gas of the liquid raw material.

Thus, the above-stated apparatus still fails to directly control the feed rate of the evaporated gas of liquid raw material; so, it remains difficult to stabilize the feed rate of the evaporated gas of liquid raw material supplied to the processing chamber.

For this reason, even when the supply of the evaporated gas of liquid raw material becomes unstable in state due to some sort of causes (such as pipe clogging due to a residual by-product material), it is no longer possible to detect such state.

This can cause the evaporated gas to be liquefied again or “reliquefied” within the pipe in which the evaporated gas is flowing, resulting in production of contaminant particles.

These particles often badly behave to block or “choke” not only the pipe but also a gas supply nozzle or the like, which is provided within the processing chamber.

When its liquid surface is varied (reduced) in accordance with the use amount of the liquid raw material, it is impossible to accurately detect the temperature of the liquid surface of the liquid raw material.

At this time, even when an attempt is made to accurately control the feed rate of the carrier gas, it is not possible to increase its accuracy.

Thus, it becomes difficult to stabilize the feed rate of the evaporated gas of liquid raw material to the processing chamber also, resulting in the lack of an ability to improve uniformity of the thickness of a film to be formed on the substrate.

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